I doubt these are particularly popular due to the drag but I am toying with the idea of fitting one (the watt & sea ones look good but rather expensive) since I don't race competitively, at the moment I'm just touring about learning the boat.

The main problem is the mounting on a mini, centreline is out due to all the stuff on the back of the boat so it would have to be outboard of the rudders and then I'm concerned it might be out of the water on one tack.

"Home made support working very good! Proto 353 is for sale with the hydrogenerator included" (Clever man with his advertising!) I asked for a better photo, because currently this is all I have to offer:

Thanks for the follow up and the question to W&S. I guess the answer will be a bit optimistic.I recentlly saw many similar supports on the 60' IMOCA currently in Les Sables for the Vendee Globe. They have 2 W&S, one on each side. The inertia is not the same as a mini, the average speed much higher, and the budget as well ...